Glyphs only showing the characters in list Mode

All of a sudden glyphs stopped showing the characters in thumbnail mode and only shows it in list mode, I’m on 1.3.7. Does anybody know how to fix that? Was working fine minutes ago, I already tried to move customFilter.plist to desktop and restart, reboot computer etc.

What was the last thing you did?

Try trashing ~/Library/Preferences/com.GeorgSeifert.Glyphs.plist, perhaps re-download and re-install.

Resize the sidebar a tiny bit. This is a know problem and is fixed in the upcoming update.